Which fuel tank is the main tank, the one behind the seat or the one under the truck?

1 Answer

Typically the main tank would be the one closest to the front of the vehicle, with the reserve being the one mounted further away.
On my 1982 Ford F-150, the main tank was the one underneath the driver's seat, while the other tank was towards the rear of the truck.

I have changed the fuel pump in the front tank twice. I don't believe the fuel pump itself is the problem. Just after putting the pump in I started the truck and it ran fine. After shutting it off a...